The public 3D and Materials panel options give the Light Settings as
Intensity (0–100 %), Rotation (-180° to 180°), Height (0° to 90°),
Softness (0–100 %) and Ambient Light (0–200 %), with the light moved to
the back or the front of the object. The 3D effects (Revolve included)
had Direction and Elevation (an azimuth and elevation), Intensity and
Ambient (0–100 %).
- Rotation turns the light round the object on the page (our reading:
0° on its right, counterclockwise); Height raises it from beside the
object (0°) to straight in front (90°); Light behind the object puts
it at the back. The light gizmo's ring and line are Rotation and
Height.
- Softness wraps the light round the object: at 0 % it falls off with
the angle as before, at 100 % it reaches nothing only straight away.
- Ambient Light runs to 200 %; faces stay no brighter than the art.
- lightRotation, lightHeight, lightBehind and lightSoftness replace
lightAzimuth and lightElevation. An earlier light is read as the same
direction, so it shades exactly as before (old and new code give the
same colours for the four effects and five lights); effect.setParams
turns a stored one into the new form before applying new values, and
the parameter description names lightAzimuth and lightElevation as the
earlier form, so effect.apply and effect.setParams still take them. The
default light is the earlier default's: Rotation 125.26°, Height 30°.
- The dialog's Lighting tab shows the settings in the documented order;
Softness, Ambient Light and Light behind the object are in every
catalog, and the unused Direction, Elevation and Ambient are gone.
Light colour, presets, several lights and shadows are not built.
The public 3D and Materials panel options give Perspective as 0° to 160°
("how close or far the object appears"); it was a 0–100 % strength, for
Revolve, Extrude & Bevel, Inflate and Rotate alike.
- The eye stands where a sphere about the object's centre, √3 times its
half size (the box around it fits inside), fills that angle of the
view: 0° is none, wider brings the eye nearer, and at 160° it is just
outside the sphere, never inside the object. The documentation doesn't
say how the angle places the eye; docs/three-d.md says this is our
reading.
- `perspectiveAngle` (degrees) replaces `perspective` (%). A strength from
an earlier file or script is read as the angle that shows exactly the
same view: sin(angle / 2) = √3 × strength / 4, 100 % about 51.3°. An
angle given too wins. effect.setParams turns a stored strength into the
angle before applying new values. The parameter description names
`perspective` as the earlier form, so effect.apply and effect.setParams
still take it under the key check of #1592. Old and new code draw the four effects identically at 0, 25,
60 and 100 % (bounds equal to 1e-9).
- The dialogs' Perspective fields run 0–160°.
# Conflicts:
# docs/target-app-parity.md
Ayberk A.